Require explanations for suppressed warnings in OTLP profiles exporter

[thswlsqls]

Related to #7874

Description

• Require explanations for suppressed warnings in logging OTLP #8741 enabled the SuppressWarningsWithoutExplanation ErrorProne check for exporters/logging-otlp and added a temporary opt-out to every other module. This does the same for :exporters:otlp:profiles.
• Removes otelJava.requireSuppressWarningsExplanation.set(false) from build.gradle.kts, so the default convention(true) applies.
• Adds an explanation to the @SuppressWarnings("unchecked") in ProfilesRequestMarshalerTest#parse, the one suppression here the check flags. Same form as the comments Require explanations for suppressed warnings in logging OTLP #8741 added.
• The module's other two suppressions (ReferenceEquality, AvoidObjectArrays) are out of scope: the check only flags deprecation, rawtypes and unchecked.
• This covers one module, so the issue stays open.

Testing done

• Build flag and one comment only, so no test added.
• ./gradlew :exporters:otlp:profiles:check — BUILD SUCCESSFUL.
• Confirmed the check is live: with the flag removed but the comment reverted, compileTestJava fails with one SuppressWarningsWithoutExplanation error, at ProfilesRequestMarshalerTest.java:475.
• No apidiff change: alpha artifact, public API untouched.

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Waiting on reviewers · refreshed 2026-09-02 14:35 UTC

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.29%. Comparing base (e2efec5) to head (2160866).

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #8747   +/-   ##
=========================================
  Coverage     91.29%   91.29%           
  Complexity    10498    10498           
=========================================
  Files          1006     1006           
  Lines         28338    28338           
  Branches       3581     3581           
=========================================
  Hits          25870    25870           
  Misses         1675     1675           
  Partials        793      793           

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